The plane л has equation x + 2y + 3z = 7.
(a) Calculate the acute angle between л and the plane z = 0, giving your answer correct to the nearest 0.1°.
(b) Determine the coordinates of the point A in such that the line joining the origin to A is perpendicular to л. Hence, show that the perpendicular distance from the origin to is 1/(2√14).​